Today, some of the players might be experiencing trouble logging into Call of Duty: Black Ops II or Battlefield 4 on their Xbox 360, but that is not an issue of your console or your internet connection but the maintenance that is being done by the developers and everything will be up and running really soon.
You might not be able to access most of the features of the game or might experience a trouble playing with someone on the Xbox Live but as soon as EA and Activision are done with the maintenance, you will be able to play the game just fine.
Meanwhile, you can take a break from the FPS games and try out other games that have been sitting on your shelves for quite some time or play the single player campaign for the titles, until the issues are fixed.
Xbox Support states the problem as:
Are you having connection issues while playing Call of Duty: Black Ops II or Battlefield 4? Don’t worry, this is due to maintenances our partners are performing. Thanks for your patience! We’ll provide an update when more information is available.
Are you facing any problem in Call of Duty Black Ops 2 or Battlefield 4? Let us know in the comments!
Source: Xbox Support